this npm module includes a json shell command. the json command processes standard
input and parses json objects. json currently handles a few different standard
input formats and provides a number of options tailored toward inspecting and
transforming the parsed json objects.

-h print help info and exit
-v (-V | --version) print version number and exit
-u print ugly json output, each object on a single line
-d print debugging output including exception messages
-o object.path specify the path to an array to be iterated on
new.key=old_key move old_key to new.key in output object
-a input object is an array, process each element separately
-c "js conditional" js conditional to be run in the context of each object that determines whether an object is printed
-C print the output fields as tab delimited columns in the order specified by fields
-e "js expression" execute arbitrary js in the context of each object.
-i use node's util.inspect instead of JSON.stringify.
-H print headers, if they are supplied. Useful for output from curl -i.

any number of fields can be specified to be printed from each json object.
by default the structure of the original json object is maintained, however options
like -e and foo=bar allow for transforming object structure.